Intraocular lenses are routinely implanted in patients' eyes during cataract surgery to replace the natural crystalline lens. A variety of ophthalmic lenses are employed for correcting visual disorders, such as, cataract, myopia, hyperopia or astigmatism. For example, an intraocular lens (IOL) can be implanted in a patient's eye during cataract surgery to compensate for the lost optical power of the removed lens. In many cases, however, the implanted lens may not provide the best focus at the targeted object distance.
The design of modern conventional IOL optics is mainly focused on two outcomes: an optic that provides aberration correction to provide clear distance vision, or a multifocal optic that can provide far vision while also providing for near vision needs. These designs do not typically address another important patient need, namely: for most elderly patients, the majority of visual needs are focused around certain intermediate distances. These elderly patients, who form a large percentage of patients receiving IOLs to replace a natural lens, require an extended functional vision, from distance to intermediate, to perform daily chores. This extended functional vision is not sufficiently provided for by current IOL designs.
Accordingly, there is a need for an improved ophthalmic lens, and, more particularly, for an improved IOL, that can provide an enhanced depth of focus compared to prior art IOLs.